Pharmacokinetics and Bioequivalence of the Lubiprostone Capsule in Healthy Chinese Subject

This publication reports a pharmacokinetic and bioequivalence investigation of lubiprostone in healthy Chinese subjects, encompassing single-dose, food-effect crossover, multiple-dose, and formal bioequivalence study cohorts. Plasma concentrations of the active metabolite (15-OH-lubiprostone) were measured by HPLC-MS/MS and pharmacokinetic parameters calculated using Phoenix WinNonlin. The metabolite showed dose-proportional pharmacokinetics across the studied dose range, with food significantly increasing AUC and delaying time to peak concentration, and the test and reference products were shown to be bioequivalent under fed conditions. These findings characterize lubiprostone's pharmacokinetic behavior and confirm bioequivalence of the tested formulation in this population.